NEW DIELECTRIC 1-D EBG STRUCTURE FOR THE DESIGN OF WIDEBAND RESONATOR ANTENNAS

In this paper, we propose a method to use 1-D dielectric slabs, instead of metallic Frequency Selective Surfaces (FSSs), to produce Partially Reflective Surfaces (PRSs) with positive reflection phase gradients. The structure is realized by a single kind of dielectric substrate. It is modeled as cascaded transmission lines and then analyzed by virtue of the Smith Chart from the perspective of impedance transformation. A PRS designed by this approach is then applied to the realization of a wideband EBG resonator antenna operating at Ku band which is fed by a slot-coupled patch antenna. The calculated results indicate that the antenna possesses a relative 3 dB gain bandwidth of 22%, from 14.1 GHz to 17.6 GHz, with a peak gain of 17 dBi. The impedance bandwidth for the reflection coefficient (S-11) less than -10dB, is from 14 GHz to 17.7 GHz, well covering the 3 dB gain bandwidth. A prototype has been fabricated and measured, and the experimental results well validate the simulation. The design method developed here is significantly effective, and can be easily adopted for antenna designs at other frequencies.